Flooded Avenue C at East 6th Street in Manhattan's East Village neighborhood of Loisaida, moments before the Con Edison power substation on 14th Street and Avenue C blew up.David Shankbone/CC BY 3.0

Climate change is causing sea levels to rise, and this week’s super storm Sandy gave us a preview of the devastation that this kind of flooding can cause. In fact, five years ago, a study named, “Nation Under Siege” constructed a series of 3-D maps using federal science agency and the United Nations' climate panel data that demonstrated what areas of the Atlantic coastline will look like as sea levels continue to rise. The maps from 2007 are eerily similar to the destruction we saw from super storm Sandy. The main difference being that the flooding from Sandy is beginning to recede and the rising waters from global warming are permanent.

There’s no denying that sea levels are rising. Since 1900, the world’s oceans rose an average of seven inches, according to data from the UN Intergovernmental Panel on Climate Change (IPCC). Those of us that live on the East Coast are seeing higher than average sea level rise. According to a report by the New York State Sea Level Rise Task Force, sea levels along New York's coast range between 9 and 11 inches over the last 100 years.

Super storm Sandy painfully demonstrated that coastal cities are woefully unprepared for flooding and other dangers from extreme weather, which is increasing due to climate change. According to Katharine Hayhoe, an associate professor of atmospheric sciences at Texas Tech University, there are three reasons why climate change made Sandy that much worse. The first is already higher sea levels made the storm surge more severe. The second is higher sea surface temperatures from global warming provided more energy for the super storm. The third is Sandy may turned towards the coast because of a record loss of sea ice in the Arctic this year.

Preparing at-risk communities for coming floods and coastal erosion includes determining the best way to heighten sea walls or whether to construct surge barriers to protect flood-prone areas. These preparations require study and then construction costs in the billions. However, the latest estimates from IHS Global Insight, a forecasting firm, calculate that super storm Sandy will end up causing about $20 billion in property damages and $10 billion to $30 billion more in lost business. It sounds like the time is now to make those investments before further extreme weather from global warming costs more in the long run. We can couple those investments with our own efforts to lower our carbon footprints, which contributes to slowing down climate change.